Handling aid utilizing vacuum operated counterbalance

ABSTRACT

A handling aid for lifting heavy objects comprises a vacuum chuck and a vacuum operated counterbalance which is operational only when the chuck engages an object to be lifted. The counterbalance comprises essentially a piston connected to a lifting arm and a vacuum operated valve, which valve is controlled by the vacuum chuck.

IJnited States Patent Gartner et al.

[ 51 July 17,1973

HANDLING AID UTILIZING VACUUM OPERATED COUNTERBALANCE Inventors: Stanley J. Gartner; Charles L.

Gearhart, both of Emporium, Pa.

GTE Sylvania lncorporated, Seneca Falls, N.Y.

Filed: Mar. 31, 1972 Appl. No.: 240,206

Assigncc:

U.S. Cl. 214/1 BH, 214/1 BV Int. Cl. B66c 1/02 Field of Search 214/1 BS, '1 EV, 147 T,

References Cited UNITED STATES PATENTS 12/1951 Rooksby 214/147 T X 2,792,810 5/l957 Maconeghy 2l4/l BV Primary Examiner-Gcrald M Forlcnzu Assistant ExaminerGcorgc F. Abraham Attorney-Norman J. ()Malley. William H. McNeil! ct al.

[57] ABSTRACT A handling aid for lifting heavy objects comprises a vacuum chuck and a vacuum operated counterbalance which is operational only when the chuck engages an object to be lifted. The counterbalance comprises essentially a piston connected to a lifting arm and a vacuum operated valve, which valve is controlled by the vacuum chuck.

6 Claims, 11 Drawing Figures Plume July 11, 1973 3,746,185

5 Sheets-Sheet 2 Patented July 17,1973 3,746,185

5 Sheets-Sheet 5 Patented July 17, 1973 5 Sheets-Sheet 5 HANDLING AID UTILIZING VACUUM OPERATED COUNTERBALANCE BACKGROUND OF THE INVENTION This invention relates to handling aids for lifting or moving heavy objects and more specifically to such handling aids which utilize a counterbalance. Still more specifically, it relates to a handling aid whose counterbalance functions only when the aid is loaded.

The idea of counterbalancing to assist in the movement of heavy objects is, of course, centuries old. However, such counterbalances have been mechanical contrivances such as weights added beyond the pivot point of a lever. If one end of a lever arm, for example, is fashioned to pick up a heavy object, a mechanical counterbalance can be added to the other end of the lever arm to reduce the force necessary to lift or move the object. After the object has been moved to a new location and disengaged from the lifting end of the lever, the counterbalance still remains and extra force is necessary to return the lever arm to its starting position. It would be advantageous, therefore, if a system could be devised wherein the counterbalance acted only when the object was being moved.

OBJECTS AND SUMMARY OFTI-IE INVENTION It is an object of this invention to obviate the disadvantages of the prior art.

It is another object of this invention to enhance the lifting of heavy objects.

A still further object of the invention is the provision of a counterbalance-that functions only when needed to lift or move heavy objects.

Another object of the invention is the provision of a handling aid which is simple and economical to build and operate.

These objects are accomplished in one aspect of the invention by a handling aid which comprises a source of relatively high vacuum and source of relatively low vacuum. A vacuum chuck for gripping the object to be lifted is provided and is connected to the source of high vacuum and a vacuum actuated counterbalance is connected to the low vacuum source by means of a normally closed valve. Additional means connect the chuck and the counterbalance and are operable, upon engagement of the chuck with an object to be lifted, to open the normally closed valve and supply a vacuum to the counterbalance whereby the counterbalance functions to aid the operator of the chuck in lifting the object.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is an elevational view of the invention in a pickup position;

FIG. 2 is an elevational view, partially in section, of the vacuum counterbalance in a position corresponding to FIG. I;

FIG. 3v is a view similar to FIG. I but during operation;

FIG. 4 is a view similar to FIG. 2 showing the change in the counterbalance when the device is being operated;

FIG. 5 is a view similar to FIGS. 1 and 3 but showing the device in a release position;

FIG. 6 is another view of the vacuum counterbalance showing the position which corresponds to FIG. 5;

DESCRIPTION OF THE PREFERRED EMBODIMENTS For a better understanding of the present invention, together with other and further objects, advantages and capabilities thereof, reference is made to the following disclosure and appended claims in connection with the above-described drawings.

Referring now to the drawings with greater particularity, there is shown in FIG. I a vacuum utilizing handling aid 10 for lifting heavy objects, such as cathode ray tubes 12. The aid 10 comprises a source of relatively high vacuum 14 and a source of relatively lower vacuum 16. The source 16 can be a completely separate source or it can be derived from the high vacuum force 14 through a regulating valve 18. A vacuum actuated counterbalance 20 and a vacuum chuck 22 for contacting the object to be lifted are also provided. The vacuum chuck 22 is connected to a high vacuum reservoir or ballast tank 24 by means of a hose 26; the reservoir 24 being connected to the source of high vacuum by hose 27. The counterbalance 20 is connected to a low vacuum reservoir 28 through a normally closed valve 30 and hose 31; the reservoir 28 being connected to the low vacuum source 16 through regulator valve 18.

The aid 10 is articulated for movement, e.g., by mounting low vacuum reservoir 28 for movement in a horizontal plane by means of bracket 32 affixed to one end thereof. The bracket 32 is provided with bushings 34 which journal a vertically mounted shaft 36 which is fastened to an upright support 38.

The other end of reservoir 28 is provided with a bracket 40 on which is pivotally mounted a vertical shaft 42. The lower end of shaft 42 that allows for horizontal movement of the aid 10 mounts a bracket 44 at one end thereof while the other end of bracket 44 is pivotally connected to one end of reservoir 24 allowing the same to pivot in a vertical plane. A bracket 46 on one end of counterbalance 20 is fixed to bracket 44 intermediate the ends thereof.

The counterbalance 20 (FIG. 2) comprises a cylinder 48 having first, second and third chambers 50, 52, and 54 respectively. The first chamber 50 contains a piston 56 having a head 58 and a projection shaft 60 connected thereto. The free end of shaft 60 is pivotally connected to a fixed bracket 62 on reservoir 24.

The second chamber 52 contains a normally closed two-way vacuum valve 64 which has a valve stem 66 positioned within the second chamber and having a first valve head 68 positioned within first chamber 50 and a second valve head 70 positioned within third chamber 54. The valve heads are to seal or open ports 72, 74 respectively. The third chamber 54 is connected to the low vacuum source 16 by hose 3]. A second 76 of the third chamber 54 which is sealable from the remainder of the chamber by second valve head 70, is formed with a by-pass 77 which interconnects the third chamber 54 and the first chamber 50.

collar 78 which is fixed to valve stem 66 intermediate the valve heads thereof. A flexible diaphram 80 is affixed to the collar and extends to the walls 82 of second chamber 52 forming an enclosed part 84 of the second chamber 52 which is not open to atmosphere from an open port 86 which admits atmosphere by means of apertures 88. Port 86 is adjacent first chamber 50. A spring 90 is positioned between the collar 78 and wall 92 which divides the second and third chambers whereby the two-way valve 64 is normally positioned so that atmosphere can enter first chamber 50 via apertures 88 in second chamber 52 and port 72. The enclosed port 84 of second chamber 52 is provided with a connection to the high source of vacuum 14 via hose 94 and chuck 22 as will be explained hereinafter.

The chuck 22 comprises a body 96 having a peripheral vacuum skirt 98 formed at one end thereof. The skirt 98 is of suitable material such as heavy rubber or vinyl which will form an airtight seal with the article to be lifted. Located substantially centrally of body 96 is a piston 100 which is spring loaded downwardly, as by means of spring 102 to normally seal off high vacuum paths 104 and 106 which are formed within body 96. At least one aperture 108 opens the high vacuum paths to the area enclosed by skirt 98. Body 96 is further provided with a release valve 110 in the form of a handle 112 which contains a pathway 114. The position of handle 112 controls the entrance of the atmosphere to body 96 as is shown in FIGS. and 11. The source of high vacuum 14 is connected to chuck 22 via reservoir 24 and hose 26, the latter connecting with vacuum path 104 within body 96. Path 106 connects, via hose 94, to a second chamber 52 and the valve actuating means contained therein.

The piston comprises a cylindrical body which contains an open ended hollow 116 for spring 102 which is constrained at its other end by a plate 118 fastened to body 96. An actuating member 120 having a rubber or other suitable material tip 122 is connected to piston body l 14 by a shaft 124. The piston body 115 slides in port 125 into which vacuum paths 104 and 106 connect. In its normal, or closed, position the body 115 is downwardly positioned and seals the vacuum paths.

For a complete understanding of the invention a sequence of operation will be described. At the start of the lifting operation the aid 10 is in the general position shown in FIG. 1, ready to pick up an object to be moved, such as cathode ray tube 12 in stand 13. The vacuum chuck 22 is in the position shown in FIG. 7; i.e. the piston 100 is down and the vacuum being draw from source 14 is deadended at the terminus of path 104. Similarly, no vacuum is being drawn through hose 94 and path 106 nor through aperture 108. Handle 112 is in the up position and is closed to the atmosphere.

The counterbalance is in the position shown in FIG. 2, i.e., the low vacuum to third chamber 54 is deadended by virtue of valve head 70 being seated in port 74. Thus, air can enter first chamber 50 via the apertures 88 in second chamber 52 and the open port 72, the low vacuum being drawn in the third chamber 54 being insufficient to overcome the force of the spring 90. With the first chamber 50 thus being open to air there is no force exerted upon the face of piston head 58.

Y To begin operation an operator will manually move chuck 22 until it contacts the object to be lifted, in this case tube 12. Upon contact of the tip 122 of actuating member 120 with a surface of the tube 12 piston 100 is displaced upwardly to open the paths 104 and 106 to the source of high vacuum via hose 26 and reservoir 24. This, of course, allows vacuum to be drawn through ap erture 108 and upon contact of the skirt 98 with the tube 12 supplies vacuum to the area surrounded by the skirt 98 and allows the tube 12 to be held by the chuck 22. Occurring simultaneously, the high vacuum is drawn through path 106 and hose 94 and is thus applied to closed port 84 of second chamber 52. This vacuum force is exerted against diaphram and overcomes the force of spring moving two-way valve 64 to the right. This action seats valve head 68 in port 72 and removes valve head 70 from port 74 thereby clos ing off first chamber 50 from the atmosphere and applying thereto a source of low vacuum via by-pass 77, section 76 of third chamber 54, hose 31 and reservoir 28. When the operator lifts the tube 12 by grasping chuck 22 the vacuum being applied to the face of piston head 58 urges the head 58 to the right thus exerting lifting pressure upon reservoir 24, which is acting as a lever, through piston shaft 60 and its connection to bracket 62. To further aid in lifting, another fixed bracket 126 can be afiixed to reservoir 24 and have a spring 128 attached between it and bracket 44. This second-described position of the operative elements is shown in FIGS. 3, 4, and 8. When the tube 12 is in its desired position; e.g., in a suitable aperture 130 in carrying tape 132 (see FIG. 5) the operator moves handle 112 to the dump" position shown in FIG. 10. This action allows air to enter paths 104 and 106 through pathway 114 and aperture 134 in valve 1 10 thus destroying the vacuum and releasing the tube 12. As the vacuum is destroyed, spring 90 exerts pressure against collar 78 returning two-way valve 64 to its normal position (see FIGS. 2 and 6) shutting off the low vacuum to chamber 50 and opening the same to air. At the same time spring 102 forces piston downwardly sealing off the vacuum to paths 104 and 106, and, with the return of handle 112 to the up position, the aid is ready for another cycle of operation.

It will be seen from the above that there is here provided a new and novel advance in the lifting of heavy objects. The counterbalance operates only when needed and the entire device is simple and economical to build and operate. It is to be noted that the particular articulation of the device as well as the article lifted were given herein by way of example only and are not meant to be construed as limitations in the applicability of the device.

While there has been shown and described what is at present considered the preferred embodiment of the invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the scope of the invention as defined by the appended claims.

What is claimed is:

l. A vacuum utilizing handling a aid for lifting heavy objects comprising: a source of relatively high vacuum; a source of relatively low vacuum; a vacuum actuated counterbalance; and a vacuum chuck for contacting and gripping the object to be lifted, said vacuum chuck being connected to said source of high vacuum; said counterbalance being connected to said source of low vacuum by a closed valve and means connecting said chuck and said counterbalance operable upon engagement of said chuck with an object to open said closed valve thereby supplying a vacuum to said counterbalance.

2. The invention of claim 1 wherein a high vacuum reservoir is connected between said high vacuum source and said chuck and a low vacuum reservoir is connected between said low vacuum source and said counterbalance.

3. The invention of claim 2 wherein said counterbalance comprises a cylinder having a piston movable therein, said piston having a shaft which extends beyond said cylinder and which is mounted to a first flange fixedly attached to one end of said high vacuum reservoir; said cylinder being fixed to a second flange substantially intermediately the ends thereof, the distal portion of said second flange pivotally mounting said high vacuum reservoir for vertical movement.

4. The invention of claim 3 wherein the proximal portion of said second flange is mounted to achieve horizontal movement of said high vacuum reservoir.

5. The invention of claim 1 wherein said counterbalance comprises: a cylinder having first, second and third chambers, a piston in said first chamber; a normally closed two-way vacuum valve having a valve stem positioned within said second chamber and having a first valve head positioned within said first chamber and a second valve head positioned within said third chamber, said third chamber having a connection to said low vacuum source and a by-pass connection to said first chamber, said second chamber being partially open to atmosphere and having means forming a wall of an enclosed part of said second chamber for actuating said valve.

6. The invention of claim 5 wherein said means for actuating said valve includes a collar on said stem engaging the central portion of a flexible diaphragm which extends to the walls of said second chamber forming an enclosed part of said second chamber which is not open to atmosphere; a spring between said collar and the dividing wall between said second and third chambers whereby said valve is normally positioned so that atmosphere can enter said first chamber from said second chamber; and means in said enclosed part of said second chamber connecting the same to a source of high vacuum.

2:12; UNITED STATES PATENT oFTIcE @ERTHHQATE M QQBRECTION Patent NO. 3,746,185 Dated July 17, 1973 invading) Stanley J. Gartner and Charles L. Gearhart It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 2, line 43 after "42" first instance, insert "that allows for horizontal movement of the aid 10."

C01. 2, line 43 after "42" second instance, delete I "that allows for horizontal movement of the aid 10" C01. 2, line 54 "projection" should read "projecting" Col. 2, line' 64 "second" should read "section Col. 3 line 15 "port" should read "part Col. 3, line 38 "15" should read "ll5 Signed and sealed this 16th day of December 1973.

(SEAL) Attest:

EDWARD M. FLETCHER, JR, RENE 'D. TEGTMFYER Attesting Officer ,7 Acting Commissioner of Patents J 

1. A vacuum utilizing handling a aid for lifting heavy objects comprising: a source of relatively high vacuum; a source of relatively low vacuum; a vacuum actuated counterbalance; and a vacuum chuck for contacting and gripping the object to be lifted, said vacuum chuck being connected to said source of high vacuum; said counterbalance being connected to said source of low vacuum by a closed valve and means connecting said chuck and said counterbalance operable upon engagement of said chuck with an object to open said closed valve thereby supplying a vacuum to said counterbalance.
 2. The invention of claim 1 wherein a high vacuum reservoir is connected between said high vacuum source and said chuck and a low vacuum reservoir is connected between said low vacuum source and said counterbalance.
 3. The invention of claim 2 wherein said counterbalance comprises a cylinder having a piston movable therein, said piston having a shaft which extends beyond said cylinder and which is mounted to a first flange fixedly attached to one end of said high vacuum reservoir; said cylinder being fixed to a second flange substantially intermediately the ends thereof, the distal portion of said second flange pivotally mounting said high vacuum reservoir for vertical movement.
 4. The invention of claim 3 wherein the proximal portion of said second flange is mounted to achieve horizontal movement of said high vacuum reservoir.
 5. The invention of claim 1 wherein said counterbalance comprises: a cylinder having first, second and third chambers, a piston in said first chamber; a normally closed two-way vacuum valve having a valve stem positioned within said second chamber and having a first valve head positioned within said first chamber and a second valve head positioned within said third chamber, said third chamber having a connection to said low vacuum source and a by-pass connection to said first chamber, said second chamber being partially open to atmosphere and having means forming a wall of an enclosed part of said second chamber for actuating said valve.
 6. The invention of claim 5 wherein said means for actuating said valve includes a collar on said stem engaging the central portion of a flexible diaphragm which extends to the walls of said second chamber forming an enclosed part of said second chamber which is not open to atmosphere; a spring between said collar and the dividing wall between said second and third chambers wherEby said valve is normally positioned so that atmosphere can enter said first chamber from said second chamber; and means in said enclosed part of said second chamber connecting the same to a source of high vacuum. 